__author__ = 'wangleijie'

def square(x):
    '''
    :param x: float number
    :return: square of the x;
    >>> square(2)
    4
    >>> square(3)
    9
    '''
    return x

if __name__ == "__main__":
    print "hello"
    import doctest, module
    doctest.testmod(module);
    print "hello"
else:
    print __name__

